It's just different construction pratices. The exposed tails may actualy offer better mounting options for gutters. The most relivent thing about the exposed tails is increased risk of rot behind gutters. End grain wicks moisture much more than face grain.

I think a better question is "New facia, do we need gutters".
Never been a fan of gutters, don't know why, just seems wrong. Anyway, just sayin. I'm no expert or anything.

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Re:I think a better question is "New facia, do we need gutters".ÃÂ Never been a fan of gutters, don't know why, just seems wrong. Anyway, just sayin. I'm no expert or anything.
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Just wondering: do you live in Death Valley? ;) Our gutters have been off for a year while The Husband repaired the rafter tail rot. We now have trenches cut into the soil around the foundation from the rainwater run-off.

Here is the close-up of the roof overhanging a rafter tail. Wouldn't adding fascia make the gutter stick out past the roof line? Or is that easy to fix as part of the new roof installation?

A gutter must stick out beyond the roof line so water can fall into it.

You can hang a gutter from the roof, rafter tails or a facia. It's usually a matter of appearance, the strength of the gutter and the size needed for the predicted amount of rainwater. Hung half round gutters have a smaller capacity than conventional box gutters.

To get accurate assistance you need to draw a section detail through the roof eave.

Gutter should be outside the house so that and garbage can be fall directly into it..!!

If you plan to diy on the new roof,be aware what you are asking about here is small potatoes compared to properly installing a roof. If you plan hireing the roof installed,don't even think about telling the installer how to do it. Choose a reputable roofer and let them desighn it.
The answer to your question is,"IF"the angle between tail and deck alows pushing the facia past the deck to in effect extend the deck one and five eights inches or seven eights depending on wherther you want 1" or 2" facia,that takes care of it. The new metal drip edge will cover edge of facia and a little extra revel on shingles is required. If the angle between tail and deck prevents that,you should have made it so while repairing tails. A margin of longivity protection for tails can be accomplished by adding a 1x2 man made rot proof strip at top of facia and proper flashing it.